New odour-based pesticide trialled

Scientists from Cardiff University’s School of Chemistry and Rothamsted Research have created tiny molecules which mirror a natural occurring smell known to repel insects.

Experiments showed that in all but one case, the smells repelled insects. The isolated scent actually attracted the pests, leading researchers to believe it could play a role in trapping and monitoring.

“We know that many organisms use smell to interact with members of the same species and to locate hosts of food or to avoid attack from parasites,” said Professor Rudolf Allemann who led the research. “However, the difficulty is that scientifically smell molecules are often extremely volatile, chemically unstable and expensive to re-create. This means that, until now, progress has been extremely slow in recreating smells that are similar to the original.

“Through the power of novel biochemical techniques we have been able to make insect repellent smell molecules which are structurally different but functionally similar to the original.”

Dr Michael Birkett, Head of Chemical Ecology research at Rothamsted Research added, “Odour detection in animals is an essential, sophisticated and highly selective biological process and this phenomenon can be exploited in the behavioural control of insect pests, whereby deployment of pesticides is mitigated or better targeted. I am really excited that this novel rational approach to discovering behaviour-modifying substances (aka. semiochemicals) is already unearthing molecules with unexpected activity, and that we can modify precisely the enzymes to enable clean, efficient production. This has major implications for practical deployment of semiochemicals in crops.”